dnsmasq: add uci-defaults script for ipset migration

When running sysupgrade from an existing configuration, move existing
ipset definitions to a dedicated config section. Later on, it will allow
to serve ipset as well as nftable sets from the same configuration.

Signed-off-by: Mathias Kresin <dev@kresin.me>

package/network/services/dnsmasq/Makefile

@@ -182,6 +182,7 @@ define Package/dnsmasq/install
 	$(INSTALL_DATA) ./files/dnsmasq_acl.json $(1)/usr/share/acl.d/
 	$(INSTALL_DIR) $(1)/etc/uci-defaults
 	$(INSTALL_BIN) ./files/50-dnsmasq-migrate-resolv-conf-auto.sh $(1)/etc/uci-defaults
+	$(INSTALL_BIN) ./files/50-dnsmasq-migrate-ipset.sh $(1)/etc/uci-defaults
 endef
 
 Package/dnsmasq-dhcpv6/install = $(Package/dnsmasq/install)

package/network/services/dnsmasq/files/50-dnsmasq-migrate-ipset.sh

@@ -0,0 +1,32 @@
+#!/bin/sh
+
+ipsets=$(uci -q get dhcp.@dnsmasq[0].ipset)
+[ -z "$ipsets" ] && exit 0
+
+for ipset in $ipsets; do
+	names=${ipset##*/}
+	domains=${ipset%/*}
+
+	[ -z "$names" ] || [ -z "$domains" ] && continue
+
+	uci add dhcp ipset
+
+	OLDIFS="$IFS"
+
+	IFS=","
+	for name in $names; do
+		uci add_list dhcp.@ipset[-1].name="$name"
+	done
+
+	IFS="/"
+	for domain in ${domains:1}; do
+		uci add_list dhcp.@ipset[-1].domain="$domain"
+	done
+
+	IFS="$OLDIFS"
+
+	uci del_list dhcp.@dnsmasq[0].ipset="$ipset"
+done
+
+uci commit dhcp
+exit 0